Various attempts have been made in the past to provide support platforms of extended length in automobiles which may be useful for example as the support for a cushion or mattress. U.S. Pat. No. 2,926,948 illustrates a folding seat for station wagon which may be folded down to extend the cargo support floor. A similar innovation is U.S. Pat. No. 3,097,881 for a vehicle cushion arrangement. For the special case of vehicles with engines mounted in the rear see U.S. Pat. No. 3,188,134. A car bed and playpen for children is shown in U.S. Pat. No. 2,650,374. Finally, a complex structure including a frame and folding panels which may be configured to support seat cushions, bed cushions or as a stable for use in an automobile as illustrated in U.S. Pat. No. 3,317,238.
Most of the previously developed structures do not exhibit a great deal of versatility, are mechanically complex and expensive and add a great deal of weight to the vehicle, a consideration which is becoming increasingly important as the cost of fuel increases.